Digital signal processors (DSPs) may operate as SIMD (Single-Instruction/Multiple-Data), or data parallel, processors. In SIMD operations, a single instruction is sent to a number of processing elements, which perform the same operation on different data. SIMD instructions provide for several types of standard operations including addition, subtraction, multiplication, multiply-accumulate (MAC), and a number of special instructions for performing, for example, clipping and bilinear interpolation operations.
Many DSP applications, including many speech codecs, require high performance 16-bit multiply-accumulate (MAC) operations. To achieve high performance for these 16-bit DSP applications, 64-bit SIMD instructions may be introduced. The 64-bit SIMD instructions may be used to handle media streams more efficiently and reduce register pressure and memory traffic since four 16-bit data items may be loaded into a 64-bit register at one time.
While high throughput is an important factor for achieving high performance, power consumption may also be an important consideration in designing DSPs for wireless/handheld products. Accordingly, MAC architectures which are capable of high performance with low power demands may be desirable for use in DSPs.